NATO has warned member states that if they do not deliver the troops and equipment promised months ago to the NATO force in Afghanistan, the alliance's peacekeeping mission could fail. Such a failure could damage NATO's credibility as it tries to establish a new role for itself in the post-Cold War era.

NATO is struggling to be relevant in the 21 Century. Now an alliance of 26 countries, it took over command of a 6,500 international stabilization force in Afghanistan last year in a test of its ability to face up to new security threats far beyond the borders it was set up to defend during the Cold War.

But NATO's mission in Afghanistan has run into problems. The alliance agreed to set up, by the end of next month, five reconstruction teams in the north and west of the country to provide security for aid workers and help rebuild Afghanistan It has been unable to do so because member states have failed to deliver the personnel needed to staff the units.

Even if some of those teams are set up in the coming weeks, the alliance still lacks back-up resources, like helicopters, transport aircraft and medical evacuation units that would facilitate NATO's stated goal of providing security outside the Afghan capital, Kabul, and extending the influence of the government of President Hamid Karzai into the provinces.

Dana Allin, an analyst at the International Institute for Strategic Studies in London, says NATO must beef up security in Afghanistan as the country gears up for elections in September.

?The Karzai government has sometimes been called the mayor of Kabul because so much of the countryside is just not under government control,? he said. ?And security has always been the key issue, and it's always been inadequate. There just haven't been enough troops there.?

NATO Secretary-General Jaap de Hoop Scheffer told NATO ambassadors at a closed-door meeting on Tuesday that the alliance has failed to commit enough resources to its Afghan mission and is flirting with failure. He urged the ambassadors to immediately make good on pledges of troops and equipment they made six months ago.

Analyst Jonathan Eyal, at London's Royal United Services Institute, says the allies' failure to deliver on their pledges would undermine NATO's credibility.

?The reality is that, for NATO, this is a very major test. It's not only a test of its ability to operate out of the main area of Europe, but it's also a test of whether this alliance could be useful for international security and particularly for the Americans. If it fails in Afghanistan, it would lose an enormous amount of credibility in Washington,? Mr. Eyal said.

The U-S ambassador to NATO, Nicholas Burns, has named Spain, Turkey and Germany among 10 NATO allies that he describes as having excess troop capacity that could help relieve the alliance's forces in Afghanistan.

One top NATO official says Turkey promised three helicopters to the Afghan force but told its allies it could not deliver them to Afghanistan. The official says Luxembourg then offered to pay for transporting the aircraft. But, according to the official, the Turks then said they could not afford to pay for the helicopters' maintenance. That attitude, says the official, goes against a NATO rule that individual allies must pay for the equipment or personnel they deploy abroad.

That may now change. Turkish Prime Minister Recep Tayyip Erdogan told the Wall Street Journal Friday that his country would dispatch the helicopters and increase the number of its troops in Afghanistan if it decides to take over command of the NATO force next year. And Belgium, too, perhaps responding to the Secretary-General's warning, has announced that it will double its contingent of troops in Afghanistan before the September elections.

The dire warnings from top NATO staff about a possible failure in Afghanistan come just as the allies prepare for their summit at the end of next month in Istanbul. The United States was expected to make a push for a greater NATO role in Iraq, but analyst Jonathan Eyal says he does not expect any direct military involvement by the alliance there in the foreseeable future.

?There is a feeling at NATO's headquarters that Afghanistan needs to be digested first and that Iraq is simply too much for an alliance that still has no political consensus about the purpose of the war in Iraq and about the conduct of the occupation after the end of the war,? Mr. Eyal said.

Whereas there was strong disagreement about the war in Iraq among the allies, everybody in NATO agreed with the war in Afghanistan and about the need to stabilize that country. Analyst Dana Allin believes that, as long as the Afghan situation is unresolved, it is too early for NATO to contemplate any peacekeeping role in Iraq.

?If they can't even handle Afghanistan, they're unlikely to be able to take on a decisive role in Iraq. But the point is somewhat moot because most American allies don't want to be in Iraq anyway, for reasons that are unfortunate but perhaps understandable. The situation in Iraq just doesn't look very good right now,? he added.

So, what will come out of the NATO summit next month? NATO Secretary-General de Hoop Scheffer says he wants the allies to agree that their priority must be Afghanistan and that they must fulfill their pledges to boost troops and equipment there. Anything else, says a NATO official, is secondary.